1. Field of the Invention
This invention pertains to safety devices, and more particularly to apparatus for increasing the safety of mobile storage systems.
2. Description of the Prior Art
The use of mobile storage systems to conserve valuable floor space in offices, factories, and warehouses is widespread. Mobile storage systems typically include movable carriages that are relatively long and high in relation to their width in the direction of movement along the system rails. Consequently, the possibility exists that, under certain extreme conditions, a top heavy or eccentrically loaded carriage may tip in the direction of motion.
Various equipment has been developed to reduce or eliminate the possibility of carriage tipping. In one type of design, the longitudinal distance between the carriage wheels is increased to a practical maximum. The increased wheel spread increases the carriage stability by creating an increased moment arm for resisting overturning forces.
A second type of design for preventing the tipping of movable carriages employs rigid interfitting members on the carriage and the system rails. Normally, a running clearance exists between the carriage and rail members. However, should the carriage start to tip, the carriage member contacts and is restrained by the rail member against further tipping. U.S. Pat. No. 4,618,191 discloses a satisfactory anti tip device of the second type. Although the prior anti tip designs have given good results, they possess certain disadvantages related to cost and manufacture.
Overhead style anti tip devices are also known. Those designs require several inches of overhead space, however, which is a great disadvantage.
Thus, a need exists for an improved design for increasing the stability of mobile storage system movable carriages.